Related papers: Chiral dynamics, S-wave contributions and angular …
The branching ratios of the measured decay $K_L\to\pi^+\pi^-e^+e^-$ and of the still unmeasured decay $K^+\to\pi^+\pi^0e^+e^-$ are calculated to next-to-leading order in Chiral Perturbation Theory (CHPT). Recent experimental results are…
The three-body decays $B^0_s \rightarrow \psi(2S,3S) \pi^+ \pi^-$ are studied based on the perturbative QCD approach. With the help of the nonperturbative two-pion distribution amplitudes, the analysis is simplified into the quasi-two-body…
We present a measurement of the absolute branching fraction for $D^0 -> K^- pi^+$ using the reconstruction of the decay chain $Bbar -> D^{*+} X l^- nubar $, $D^{*+} -> D^0 pi^+$ where only the lepton and the low-momentum pion from the…
We present a data-driven analysis of the S-wave $\pi\pi \to \pi\pi\,(I=0,2)$ and $\pi K \to \pi K\,(I=1/2, 3/2)$ reactions using the partial-wave dispersion relation. The contributions from the left-hand cuts are parametrized using the…
We discuss $\pi\pi$ scattering in the framework of chiral perturbation theory. In particular, we recall the predictions made some time ago for the threshold parameters and for the phase shift difference $\delta_0^0-\delta_1^1$.
The decay widths of the $\ds\to d \pi^0\pi^0$ and $\ds\to d \pi^+\pi^-$ processes are explicitly calculated in terms of our chiral quark model. By using the experimental ratios of cross sections between various decay channels, the partial…
At the present time, there are hints of new physics (NP) in several observables involving $b \to c \ell^- {\bar\nu}_\ell$ decays. In this talk, I describe measurable angular distributions for ${\bar B} \to D^* \mu^- {\bar\nu}_\mu$ and…
We present the first amplitude analysis and branching fraction measurement of the decay $D^+_s\to \pi^+\pi^+\pi^-\pi^0\pi^0$, using $e^+e^-$ collision data collected with the BESIII detector at center-of-mass energies between 4.128 and…
The recent results from Belle of the $\tau^-\to\nu_\tau\pi^-e^+e^-$ analysis has incentivated us to make a reanalysis of a former work where the Structure Dependent parts are obtained using Resonance Chiral Theory. Here we rely on the same…
We present the results of a Dalitz plot analysis of D^0 to K^0_S pi^0 pi^0 using the CLEO-c data set of 818 inverse pico-barns of e^+ e^- collisions accumulated at sqrt{s} = 3.77 GeV. This corresponds to three million D^0 D^0-bar pairs from…
The most general structure of an elastic partial wave amplitude when the unphysical cuts are neglected is deduced in terms of the N/D method. This result is then matched to lowest order, ${\mathcal{O}}(p^2)$, Chiral Perturbation…
We present measurements of the branching fractions $\BR(B^0\to D^{\ast-} D_s^{\ast+})$ and $\BR(D_s^+\to\phi\pi^+)$, based on $123\times10^6$ Y(4S)->BBbar decays collected by the BaBar detector at the PEP-II asymmetric-energy $e^+e^-$ B…
We study a new $K\rightarrow\pi\pi$ decay channel with gluons in intermediate state which is normally neglected within the factorization framework. Both short-distance and long-distance parts of the amplitude are calculated. The chiral…
We compute the branching ratio for $\Delta\rightarrow Ne^+e^-$ and $\Delta\rightarrow N\mu^+\mu^-$ in chiral perturbation theory and find that both decays should be observable at CEBAF. With sufficiently low thresholds on the $e^+e^-$…
A Roy equation analysis of the available $\pi\pi$ phase shift data is performed with the $I=0$ S- wave scattering length $a^0_0$ in the range predicted by the one-loop standard chiral perturbation theory. A suitable dispersive framework is…
We evaluate analytically the elastic $\pi\pi$ scattering amplitude to two loops in chiral perturbation theory and give numerical values for the two $S$--wave scattering lengths and for the phase shift difference $\delta_0^0-\delta_1^1$.
We report a study of the semileptonic decays $D^+\to K_S^0\pi^0\ell^+\nu_\ell$ ($\ell = e, \mu$) based on $20.3\,\mathrm{fb}^{-1}$ of $e^+e^-$ collision data collected at the center-of-mass energy of 3.773 GeV with the BESIII detector. The…
Using the CLEO-II detector at CESR we have measured the ratio of branching fractions, ${\cal B}(D^+\rightarrow K^- \pi^+ \pi^+)/{\cal B}(D^0 \rightarrow K^-\pi^+) = 2.35 \pm 0.16 \pm 0.16$. Our recent measurement of ${\cal B}(D^0…
We study the strong interaction S-wave \Lambda\pi phase shift in the region of the \Xi mass in the framework of a relativistic chiral unitary approach based on coupled channels. All parameters have been previously determined in a fit to…
Using 2.93 $\rm{fb}^{-1}$ of $e^+e^-$ collision data collected with the BESIII detector at the center-of-mass energy 3.773\,GeV, we perform the first amplitude analysis of the decay $D^+\to K_S^0\pi^+\pi^0\pi^0$ and determine the relative…